Analysis And Implementation Of Polar Code Applied In Weak Turbulence Channel

Anti-channel interference coding is one of the key technologies in wireless optical communication area(especially for near-earth turbulence channel conditions).Polar code has gradually been in a hot research in the field of anti-channel interference coding due to its advantages.However,it has not been widely researched in the field of wireless optical communication.In this way,the research on the encoding and decoding of Polar code near-earth turbulence channel has important practical significance for ensuring the performance of wireless optical communication links and promoting the application of wireless optical communication engineering.The analysis of the principle of Polar code deriving channel polarization and channel separation under the BEC channel,and defines the polarization code by using the BEC channel as a model.Then this thesis focuses on improving the performance of wireless optical communication links under the condition of near-Earth turbulence channel.Concentrated on the comparison of the characteristics of Polar coding methods such as Gaussian approximation,Monte Carlo construction and BEC approximation,the thesis completed the encode(Monte Carlo construction)design of Polar coding.On the other hand,the simulation made by MATLAB is used to analyze the performance of BP decoding,SC decoding and CA-SCL under additive Gaussian white noise channel,combined with the decoding principle selection principle such as decoding complexity and decoding delay,the design of BP based Polar decoding scheme is determined.The thesis completed FPGA-based electronics module and built a corresponding experimental platform,then carried out experimental verification work.During the 5-day long-term link level test,the experiment achieves the results of improving the 3 levels to 1E-7 under the 1E-4 level link error performance.The results show that the proposed Polar code scheme has the effectiveness of improving the performance of wireless optical communication links under the condition of near-weak turbulent channel.